A footnote in Christopher Beckwith’s The Tibetan Empire in Central Asia (1987: 142):
212 CTS, 104:3213; HTS, 135:4570; TCTC, 216:6916. These three sources quote a conversation that took place between An Lu-shan and his bitter enemy Qośu Khan that took place prior to the rebellion in the presence of Hsüan-tsung. Trying to placate Qośu, An said: “My father was an Indo-European, my mother a Turk; your father was a Turk, your mother an Indo-European.” Qośu Khan’s father was indeed a Türgiś. (Cf. Des Rotours, 1962:1-2.) In An Lu-shan’s case, the word hu [胡] (“Indo-European, especially Sogdian”) almost certainly identifies him as a Sogdian because his surname (An) was commonly used to refer to Sogdians originally from Bukhara. Hu did not mean just “Serindian” during the T’ang period, but anyone of Indo-European race (p. 1[n. 3]).
I’m sure this last line raised some eyebrows (the sin of brachycephalic grammar and all that), but those who would berate Beckwith should cluck their tongues too at the Pashtuns and Taimannîs, for “Aryan” in present day Afghan parlance means simply Afghano-Iranoid (Schurmann, 1962: 66) — if not in the exact same sense of Carleton Coon’s “Irano-Afghan” type, then nonetheless in a more-than-linguistic one (for what do the Hazaras speak?).
See also this earlier post on historical use of *arya as an Indo-Iranian self-designation.
Beckwith, C.I. (1987). The Tibetan Empire in Central Asia: A History of the Struggle for Great Power among Tibetans, Turks, Arabs, and Chinese during the Early Middle Ages. Princeton, New Jersey: Princeton University Press.
Schurmann, H.F. (1962). The Mongols of Afghanistan: An ethnography of the Moghôls and related peoples of Afghanistan. ‘s-Gravenhage: Mouton.